bellows change out and universal joint questions DP-G

jon and michie

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Hi - My question is the bellows - on my dp-g drive are now just over 2 years old if they don't appear to have hardened would they need changing?
if so what rough estimate would it cost an engineer to change them out and would a replica bellow from keyparts be as good as a Volvo ?

next part of my question is the universal joint - the boat has approx. 290 hrs use and was built in 2005 but not used till 2007 is there a high chance the joint would of worn or is it best just to get it checked while the bellow is off ?

many thanks for any help given
Jon
 
The snag with bellows is if they go the boat sinks.

The recommended interval is 2 years and when I had out drives I always followed that.

On a personal point of view I would use the Volvo part given the severity should it fail.
 
The snag with bellows is if they go the boat sinks.

The recommended interval is 2 years and when I had out drives I always followed that.

On a personal point of view I would use the Volvo part given the severity should it fail.

+1
I used official VP agents for the two year service .
They often ( with my consent after showing me ) changed out parts on a rolling basis , inc one UJ joint from memory in 9 years of ownership.
At this service they would also remove the whole leg and take into there engine shed .Strip is down get all the gears out renew any seals .While it was layed out use a micrometer and measure stuff .
Leg would come off Monday pm and be refitted Wednesday or Thursday.
Boat was out for its annual antifoul / hull polish anyhow - so all planned .

I never had a breakdown or experienced any of the problems with KAD 300 ,s and outdrives I read about all the timeon here .Coolers were done every 5 years and water pump seals if a drip was seen at the lift . Tappets every 200 hrs etc .

I had a belt snap once and carried spares soon delt with it .
Temp quage issue due to aging and heat increasing resistance in the harness - basically unfixabke .

Looking back it cost a small fortune to maintain at that dealer standard but I have no regrets .
Shaft drive MAN powered boat that replaced it is relatively as simple as wheel barrow in comparison and easy to DIY to a high standard and feels ( not actually bothered to calculate) a lot less money to maintain .

Another point worth thinking about is the service history record?
Will it achieve it asking price more so with a thick file of OEM parts ?
 
The snag with bellows is if they go the boat sinks.

Is that actually true though? If the bellows fail then I guess you could ultimately hydraulic the engine, and ruin the transmission etc - but isn't the overall integrity of the hull maintained by that gigantic o-ring in the transom shield, rather than the bellows?
 
Is that actually true though? If the bellows fail then I guess you could ultimately hydraulic the engine, and ruin the transmission etc - but isn't the overall integrity of the hull maintained by that gigantic o-ring in the transom shield, rather than the bellows?

There’s two .
The exhaust links to hydro locking the engine in theory a passage to open exhaust valves if it floods and get over the riser .
The UJ one - not familiar with the sealing mechanism behind the transom or behind the engine .You may have a point ?

I was told by Sunseeker to follow the 2 y change , otherwise if they ( did not say specifically which ) leak the boat will sink .
Although you never see them sink or I have no experience of one sinking and there’s a lot in the SoF marinas .
So interested to find the truth .

There was a thread on here recently that appeared to be a corroded UJ ( water ingress ? ) which seized or # and split the gear case at the top .But it did not sink I think .
 
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It could only sink boat if the lipseal where UJ joins tail shaft fails, still wont do the UJ much good though so dont take an unnecessary risk.
 
Is that actually true though? If the bellows fail then I guess you could ultimately hydraulic the engine, and ruin the transmission etc - but isn't the overall integrity of the hull maintained by that gigantic o-ring in the transom shield, rather than the bellows?

Some water might get past the bearing, but I'd be surprised if you actually sank that way, unless the bilge pumps were also not working.
Even so, salty water in there will wreck the UJ and the bearings, so best to have them changed every couple of years.
 
Some water might get past the bearing, but I'd be surprised if you actually sank that way, unless the bilge pumps were also not working.
Even so, salty water in there will wreck the UJ and the bearings, so best to have them changed every couple of years.

Yep, just to be clear, I'm not advocating not replacing the bellows (I inspect my own every year, and replace every 2 years) - I'm just questioning the statement that bellows failure = sunk boat.
 
J
Think it needs 2 points of failure (bellows and shaft seal) and even then I don't think it would be a rapid event.

my own experience of bellows failure many years ago was that i could hear a trickle of water when I lifted the hatch.
I organised a rapid lift out (typically it happened on a Sunday afternoon) to discover a split in the bellows that was leaking past the seal on the intermediate shaft.
Would have been a problem if left for a long time and the bilge pump/battery failed.
 
Is that actually true though? If the bellows fail then I guess you could ultimately hydraulic the engine, and ruin the transmission etc - but isn't the overall integrity of the hull maintained by that gigantic o-ring in the transom shield, rather than the bellows?

Your sort of right , luckily Volvo drives don’t let water in a a rate where it would sink . The bearing inside the bobtail housing would have to rust away first which would take years.

Back to the OP, change your bellows and clips every 2 years and fit genuine Volvo bellows .

Change the clips every year, the latest ones are very poor, some corrode at the screw in a year especially the water pipe clip which leads to overheat when on the plane .
 
Thanks for the replies so far especially paul - last 2 seasons i checked and the bellows seemed fine as they were quite soft and not hard and rigid hence no change.
Just thinking now maybe that time to change out and check the condition of the u.j

Jon
 
Thanks for the replies so far especially paul - last 2 seasons i checked and the bellows seemed fine as they were quite soft and not hard and rigid hence no change.
Just thinking now maybe that time to change out and check the condition of the u.j

Jon
Good forum advice above but your test of "quite soft and not hard" is not a reliable and recognised test. Follow the 2 yr rule regardless. Good point about clip change every year. I've had clips go.
 
Thanks David.
So my next part of my question is does the leg need to be completely removed or can it be done in situ?
And does anyone have a rough idea on cost?
Jon
 
Even though the bellows look okay to you, they should be changed. In my experience a few years ago during my regular two year bellow change, we found one had a pin hole in it but hadn't filled with water, just moisture, no harm done. I was thankful I followed volvo's recommended maintenance schedule, dread to think what could have happened if left another year, and they did otherwise look fine ie not hardened etc.
 
Thanks David.
So my next part of my question is does the leg need to be completely removed or can it be done in situ?
And does anyone have a rough idea on cost?
Jon
The Volvo guys who do mine in Spain don't take the leg off but split the case. I think it's a recognised way of doing it (interested in volvopauls comment) but you will need to pressure test the unit on reassembly. Can't give you a cost because my bill (in Spanish) is wrapped up with all sorts of other stuff
I've done the job once myself by taking the leg off. Very heavy and not pleasant.
 
I've done the job once myself by taking the leg off. Very heavy and not pleasant.

Same here - I couldn’t walk properly for a few days afterwards, and vowed to always let someone else do it. The pros use a special cradle to hold the drive in the right position to reassemble.
 
Splitting the leg is not a great way of doing it. More chances of future leaks and also more chance of getting dirt in there. You should be removing all the pins that attach the drive to grease them anyway.
 
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